Yuanzineng kexue jishu (Jul 2023)
Macroscopic Validation and Analysis of CENDL-3.2 56Fe Nuclear Data-Based on Criticality Benchmark
Abstract
The latest version of CENDL database, CENDL-3.2, was released in 2020 with the significant changes in 56Fe nuclear data compared with ENDF/B-Ⅷ.0, the latest version of ENDF/B. In order to determine the effect of the changes on the effective multiplication factors, thirty-eight criticality benchmarks were selected for validation and analysis, including twenty-five highly enriched models, eight plutonium mental models and five other models. Then, thirty-eight criticality benchmarks were modeled in Monte Carlo program and calculated with complete ENDF/B-Ⅷ.0, and with hybrid ENDF/B-Ⅷ.0 with CENDL-3.2 56Fe nuclear data substituted, respectively. The calculation results of the effective multiplication factors show that the relative biases of CENDL-3.2 are within range of -1 046-1 955 pcm and the difference of relative biases between CENDL-3.2 and ENDF/B-Ⅷ.0 is within range of -381-290 pcm. And the relative biases of CENDL-3.2 and ENDF/B-Ⅷ.0 are basically within three standard deviations. Furthermore, the effective multiplication factors of ENDF/B-Ⅷ.0 are closer to the benchmark values for highly enriched uranium models and plutonium mental models. The effective multiplication factors of ENDF/B-Ⅷ.0 have better consistency for highly enriched models, and the effective multiplication factors of CENDL-3.2 have better consistency for plutonium mental models. Apart from this, the calculation results of main cross section sensitivity coefficients show that five of the thirty-eight models are not iron sensitive and the effective multiplication factors are primarily influenced by the 56Fe elastic scattering cross section, inelastic scattering cross section and radiative capture cross section. If the increment of the effective multiplication factors produced by the change of the elastic scattering cross section is larger than the decrease produced by the change of the inelastic scattering cross section and the radiative capture cross section, absolute bias is positive. Otherwise, absolute bias is negative.
